Reflector-cluster.



A. MY TTTTT REFLECTOR CLUSTER. APPLICATION FILED AUG. 12,1910.

OTIS A. MYGATT,. OF.NEW YORK, N. Y.

REFLECTOR-CLUSTER.

Specification of Letters Patent. PatentedJ l 28- 1914 Application filed August 12, 1910. Serial No. 576,849.

To all whom it may concern Be it known that I, OTIS A. MYGATT, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Reflector- Clusters, of which the following is a specification, reference being had therein to the accompanying drawings,

The object of the present invention is to make a reflector for a cluster of electric lamps so that that part of the reflector adjacent to each lamp of the cluster may act as a separate reflector for the lamp it covers. The prisms or specular surfaces are arranged on the surface of the reflector to obtain the greatest reflecting efiiciency and therefore the most advantageous lighting results from the particular lighting source nearest them.

When clusters of lamps are used with one large reflector covering the same having double reflecting prisms on its surface, it is impossible to get a high light reflecting efliciency from such a combination because the prisms which are ordinarily made to radiate from the center of the reflector out toward the edge, are only eflicient in reflecting light where they lie in planes passing through the axis of the light source.

Figure l is a bottom view of the conventional prism glass cluster now in use. Fig. 2 is a bottom view of one of my improved forms. Fig. 3 is a horizontal cross section of a cluster for a globe made according to my invention.

In Fig. 1 is illustrated a reflector of the ordinary type having four lamps placed beneath it. This reflector has the usual double reflecting prisms radiating from the center. The only prisms that are doing efficient work are the prisms l, 2, 8 immediately above the sources of light, as these are the only prisms lying in planes passing approximately through the axis of the light source, and are therefore the only prisms that the light rays strike at approximately the right angle in order to get the double reflection necessary for efliciency for socalled double reflecting prisms. The prisms lying between those indicated at 1, 2, 3, are not doing efficient work, and therefore the total efficiency of the prismatic reflector, when used withclusters, has not been as high as it should be.

In Fig. 2 I show a reflector body made according to my invention and arranged in a series of curves or scallops. In this arrangement each scallop as A. B acts as a separate reflector for the lamp it covers, although it can be said to be a part of the integral glass reflector. The prisms radiate from either a center above the light source or preferably from above the center of the lamp sockets. The surface of these scallops are curved around the light source and the prisms are approximately of double reflecting angles.

Fig. 3 is a horizontal sectional view of a globe or shade containing a plurality of lamps. A separate series of prisms in this case is independently calculated about each of the lamps C and D to give the maximum of reflection at approximately right angles to the light rays. A. similar disposition is made where there are more than two lamps in the globe or shade cluster. The reflectors may be made of transparent glass with a specular surface of any material whether tinted or otherwise.

Having described my invention, what I claim is:

1. In a lighting system,the combination of a plurality of light sources and glass reflecting means above the light sources, said means being provided with reflecting prisms arranged in groups, the prisms of each group being disposed to give the most advantageous lighting results with reference to the nearest light source.

2. In lighting appliances, the combination of a plurality of incandescent bulbs, and a glass reflecting body above the bulbs, said body being provided with the reflecting prisms arranged in groups, the prisms in each group being disposed at suitable angles to give proper reflection with respect to the bulb nearest them.

3. Ina lighting appliance, the combina- In testimony whereof I affix my signature tion of a plurality of light sources, and an in presence of two Witnesses.

integral glass reflecting body above said TI A MY ATT sources, having specular surfaces arranged O S G above each of the sources to give the most W1tnesseS:

advantageous llghtlng results With reference J OEL B. LIBERMAN,

to that source. ERNEST P, RAY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

